who passed away at 94 in January — was already at death’s door.“I was not expected to live,” says Poitier in the new documentary “Sidney,” which premieres on Apple TV+ on Friday. “I was born two months premature.”The film traces Poitier’s remarkable journey from his father tucking him into a shoebox as a sickly infant to growing into a screen icon and the first black man to win the Best Actor Oscar, with “Lilies of the Field” in 1964.“I remember thinking, ‘If he could do that, I wonder what I can do,’ ” says Oprah Winfrey, who produced the documentary, about how Poitier’s groundbreaking career inspired her.“It was the first time I’d seen a black man assert his power,” says Halle Berry — who became the first African-American woman to win the Best Actress Oscar in 2002 — of Poitier’s impact on her.